Was shooting today, decided to dust off an old reliable load and clock it in my new barrel. 1st 2 rounds were spot on for accuracy & speed, clocked right @ 2750 fps. Round #3 was a bit stiff & I felt a gritty blowback pepper my face, extraction of the fired case was okay, maybe just a touch sticky.
Check the pics. Dang near a case head separation.
Other than the ammo being 13 years old & having a new stainless 26" barrel on the M-77, I've shot this same load for decades.
The IMR 4831 looks to be from 2000 & 2003.
The one factor could be I switched from a CCI 250 to the Fed 215 on this box. I'm pretty damn surprised looking at that, I hardly ever change a component on a proven load..... (That could be it right there)
I'm sure my CCI 250 primers were never that mashed, I'd have backed off the load if they were.
That, and it was 85 degrees today @ the range. Most times I shoot it, 45-65 degrees.
That load is max with standard primers (Nosler data). Instead of trying to figure out what happened, I'd suggest starting over with load development for the new barrel and pull that old ammo down, save the bullets, and sh*tcan that brass, especially if it was loaded a few times.
Personally, I'd never use max (or over-max) level reloads in a rifle they weren't developed in. Just looking for trouble. Looks like you found it.
That load is max with standard primers (Nosler data). Instead of trying to figure out what happened, I'd suggest starting over with load development for the new barrel and pull that old ammo down, save the bullets, and sh*tcan that brass, especially if it was loaded a few times. Personally, I'd never use max (or over-max) level reloads in a rifle they weren't developed in.
Just looking for trouble. Looks like you found it.
Yes sir, I think your right. Good wake up call for me.
My old barrel was the blued 22" Ruger tube from 1982. This same load but using the CCI 250's was worked up in it & was completely safe & reliable, primer edges had a bit of radius on them & it would group 1-1.25" MOA consistently.
This brass had been fired 3-4x, but primer pockets were still tight. I'm going to tear the remaining 17 rounds down & restart the load, will try the Federal 210m standard primers 1st.
I wouldn't reuse that brass on a dare. After pulling your loads down, check the inside of the cases with a paper clip or dental pick. Wouldn't be surprised if you can feel a ring inside one or more.
Careful, chicken-hearted, and wise reloaders trash all the cases in a batch at the first sign of stuff like you experienced. When you load hot, you can't expect to get long case life.
Start with new brass, and size it just enough to chamber easily in the new barrel. Look up partial sizing if you're not familiar with that.
I wouldn't reuse that brass on a dare. After pulling your loads down, check the inside of the cases with a paper clip or dental pick. Wouldn't be surprised if you can feel a ring inside one or more.
Careful, chicken-hearted, and wise reloaders trash all the cases in a batch at the first sign of stuff like you experienced. When you load hot, you can't expect to get long case life.
Start with new brass, and size it just enough to chamber easily in the new barrel. Look up partial sizing if you're not familiar with that.
Yup, tossed that brass. Have a few bags of new stuff on hand.
I suppose, but I think that's supposed to be more likely with squeaky clean case necks, unlikely with brass loaded that many times unless the OP is a clean freak.
I had that happen once , I found out that I had a shell holder that was was short and caused a head space problem when I full length resized my brass. The shell holder and a bunch of brass went in the garbage and the problem went away.
"Before you criticize someone, walk a mile in their shoes. That way, you'll be a mile from them, and you'll have their shoes."
Full length resized each time, never turn my necks. I do keep them trimmed down to the suggested trim to length though. Never had to anneal necks on my 270 brass like I did with the .243 target rifle but I was reloading that brass up to 10x with the mild loads I was running.
So I'd guess I'd use the 270 brass a maximum of 5 reloads then toss it due to enlarged primer pockets. Never seen a split neck or shoulder in 35 years on my 270 brass.
I had that happen once , I found out that I had a shell holder that was was short and caused a head space problem when I full length resized my brass. The shell holder and a bunch of brass went in the garbage and the problem went away.
That almost happened to me. I inherited a bunch of equipment from my brother. Among it was a shellholder he had ground down for some reason. Fortunately, I ran the cases through a gauge before loading and shooting them. Also fortunate us that they were from a mixed group of once-fired Feds from my big stash of .270 brass and not new cases.
I sometimes wonder about the necessity of loading up "max loads" . I have never met an elk, deer or pronghorn that complained about the lack of 100FPS in my loads. Backing off a little never hurt anything and results in longer case life, along with longer barrel life.
“The one factor could be I switched from a CCI 250 to the Fed 215 on this box.”
“Other than the ammo being 13 years old & having a new stainless 26" barrel on the M-77, I've shot this same load for decades.”
“That, and it was 85 degrees today @ the range. Most times I shoot it, 45-65 degrees.”
Three strikes and you are out! But you were very lucky. Should have bought a lottery ticket on the way home.
REMEMBER: When you change any component, drop back to an entry level load and work up. New barrel = new chamber = new gun=start load development again. Don’t shoot cool weather max loads in hot weather.
We are glad you posted this to help us watch our loads too.
I had a .270 Ruger that had such generous chamber dimensions that neck sized brass would not fit in the other 270s. I don't think going to an AI would have cleaned it up with out setting the barrel back several threads. Most expansion was in the base area. If yours is like that you are working the web area each time you FL size it. Brass can age harden especially if subject to any heat. Also any fumes can weaken the brass. I left some muriatic acid open and cartridges stored on the shelf below had to be chucked.
Just for grins I would check both chambers or compare fired brass to see how far off they are if any.
"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli
Case head separations are caused by excessive head clearance which means either the rifle chamber is too long in headspace or the cartridge is too short. Headspace or, more properly, head clearance, is also the cause of the excessively flattened primers. I suspect the brass is being sized too much so that the shoulder is being set back. Back your FL die out about a 1/2 turn, size a case, and see if it goes into the chamber with little resistance. If there is some resistance, turn the die in 1/8 turn and repeat the test. Do this until you reach the point where there is just a hint of "feel" as you close the bolt. You can then lock the ring in this position and your brass life will be much improved. The 270 has a decently long neck and some taper to the body so it lends itself well to partial sizing. After I have set the die up as described, I then put a washer which 1/10 inch thick beneath the lock ring for most of my loading (the decapping rod may ave to be turned in a bit). This will really improve your brass life and will reduce the amount of trimming necessary. A second point which I have to mention is, if you are seeing enlarged primer pockets after just a few firings, the load is too hot for the brass. Pockets may eventually loosen due to wear but this takes a lot of loading. Otherwise, enlargement means the pressures have exceeded the elastic limit of the brass. GD
(That could be it right there)
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